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 A HISTORY OF SURREY from Ockham Common (Lucas) i, Heptagenia sulpburea, Mull., from Walton- on-Thames (Annett), and C. dipterum, Linn., complete the scanty list. Excepting perhaps Hampshire, no county probably has so rich a dragonfly fauna as Surrey. The numerous tributaries of the Thames, meandering through the county and on their way traversing a variety of geological formations, are the abode of the nymphs of many species, while the insects that throng the vicinity of their banks provide exhaustless provender for the perfect dragonflies to which the nymphs give birth. Even the Thames. itself, before it becomes a tidal river, has a certain limited dragonfly fauna also. But the numerous lakes and ponds in park, wood, or common, that are found throughout the country are the happy hunting-ground of the odonatist. Those situated in fir woods seem to be most prolific, a little group near Ripley that has been well worked having produced twenty-three species, and a single one some six miles distant twenty-one, the total for the county being thirty, out of a total for the whole of the British Isles of forty-one. That there is plenty of scope for fresh workers nevertheless is quite evident, seeing that but a small minority of these lakes and ponds have been systematically worked in connection with their dragonfly inhabitants, even if some of them have been visited for that purpose at all. The Basingstoke Canal, which however is most uncanal-like in its surroundings, is another good locality, and no doubt other canals of a similar character would well repay the attention bestowed upon them. Of the dragonflies not so far recorded for Surrey, four Leucorrbinia dubia, Lind., Somatochlora metallica, Lind., S. arctica, Zett., and Mscbna carulea, Strom are northern species, and therefore not likely to occur ; but there seems to be no intrinsic reason why the others should not be found. Of the conspicuous species, Oxygastra curtisii, Dale, and /Escbna isosceles, Mull., however, it is probably safe to say that they are absent. The case is different with Libellula fufoa, Mull., Lestes dry as, Kirb., Iscbnura pumilio, Charp., Agrion hastulatum, Charp., and A, mercurials, Charp. Unless carefully examined they so closely resemble neighbouring species that they may very well have been passed over. Collectors there- fore should always make it a point to look out for, and catch as suspects, all dragonflies that resemble them, especially in new localities. Libellulints. All the British species of the in 1898 (Lucas), and the species occurred genus Sympetrum have been taken in the again in 1899 and 1900, while one was county. S. striolatum, Charp., is no doubt seen (Lucas) in 1898 at Elstead. In each present everywhere in suitable localities from year all taken were males, and these again the end of June till as late as mid-November were probably immigrants. A few 5. san- under favourable circumstances. Its very guineum, Mull., were taken on Ockham close relative, however, S. -uulgatum, Linn., Common in 1898 1900 (Lucas), though they has been taken but twice a male on Book- were not noticed there previously. 5. scoticum, ham Common in 1891 (Briggs), and another Don., is widely spread throughout the county male in Richmond Park in 1898 (Lucas), in suitable localities ponds and pools on Of S.fonscolombii, Selys, seventeen males were swampy heaths. Libellula depressa, Linn., is taken on Ockham Common in June, 1892 a common, widely distributed insect flying in (Briggs), their presence being no doubt due to the spring, and here again no localities need be immigration. 5. flaveolum, Linn., was met given. L. quadrimaculata. Linn., is more local, with in fair numbers on Ockham Common though usually common where it occurs. It 78